Scientists from Seattle Children’s Research Institute and the University of Washington, in collaboration with the Genomic Disorders Group Nijmegen in the Netherlands, have identified two new genes that cause Baraitser-Winter syndrome, a rare brain malformation that is characterized by droopy eyelids and intellectual disabilities.
“This new discovery brings the total number of genes identified with this type of brain defect to eight,” said William Dobyns, MD, a geneticist at Seattle Children’s Research Institute. Identification of the additional genes associated with the syndrome make it possible for researchers to learn more about brain development. The study, “De novo mutations in the actin genes ACTB and ACTG1 cause Baraitser-Winter syndrome,” was published online February 26 in Nature Genetics.
The brain defect found in Baraitser-Winter syndrome is a smooth brain malformation or “lissencephaly,” as whole or parts of the surface of the brain appear smooth in scans of patients with the disorder. Previous studies by Dr. Dobyns and other scientists identified six genes that cause the smooth brain malformation, accounting for approximately 80% of affected children. Physicians and researchers worldwide have identified to date approximately 20 individuals with Baraitser-Winter syndrome.
While the condition is rare, Dr. Dobyns said the team’s findings have broad scientific implications. “Actins, or the proteins encoded by the ACTB and ACTG1 genes, are among the most important proteins in the function of individual cells,” he said. “Actins are critical for cell division, cell movement, internal movement of cellular components, cell-to-cell contact, signaling and cell shape,” said Dr. Dobyns, who is also a University of Washington professor of pediatrics. “The defects we found occur in the only two actin genes that are expressed in most cells,” he said. Gene expression is akin to a “menu” for conditions like embryo development or healing from an injury. The correct combination of genes must be expressed at the right time to allow proper development. Abnormal expression of genes can lead to a defect or malformation.
“Birth defects associated with these two genes also seem to be quite severe,” said Dr. Dobyns. “Children and people with these genes have short stature, an atypical facial appearance, birth defects of the eye, and the smooth brain malformation along with moderate mental retardation and epilepsy. Hearing loss occurs and can be progressive,” he said.
Dr. Dobyns is a renowned researcher whose life-long work has been to try to identify the causes of children’s developmental brain disorders such as Baraitser-Winter syndrome. He discovered the first known chromosome abnormality associated with lissencephaly (Miller-Dieker syndrome) while still in training in child neurology at Texas Children’s Hospital in 1983. That research led, 10 years later, to the discovery by Dobyns and others of the first lissencephaly gene known as LIS1.
Dr. Dobyns’ co-authors on this study include: Jean-Baptiste Riviere, PhD, Seattle Children’s Research Institute; Christopher Sullivan, Seattle Children’s Research Institute; Susan Christian, Seattle Children’s Research Institute; Brian O’Roak, PhD, University of Washington; Jay Shendure, MD, PhD, University of Washington; and many other physicians and scientists from North America and Europe.Additional Resources
Mary Guiden | EurekAlert!
Superresolution live-cell imaging provides unexpected insights into the dynamic structure of mitochondria
18.02.2020 | Heinrich-Heine-Universität Düsseldorf
Blood and sweat: Wearable medical sensors will get major sensitivity boost
18.02.2020 | Moscow Institute of Physics and Technology
Most natural and artificial surfaces are rough: metals and even glasses that appear smooth to the naked eye can look like jagged mountain ranges under the microscope. There is currently no uniform theory about the origin of this roughness despite it being observed on all scales, from the atomic to the tectonic. Scientists suspect that the rough surface is formed by irreversible plastic deformation that occurs in many processes of mechanical machining of components such as milling.
Prof. Dr. Lars Pastewka from the Simulation group at the Department of Microsystems Engineering at the University of Freiburg and his team have simulated such...
Investigation of the temperature dependence of the skyrmion Hall effect reveals further insights into possible new data storage devices
The joint research project of Johannes Gutenberg University Mainz (JGU) and the Massachusetts Institute of Technology (MIT) that had previously demonstrated...
Researchers at Chalmers University of Technology, Sweden, recently completed a 5-year research project looking at how to make fibre optic communications systems more energy efficient. Among their proposals are smart, error-correcting data chip circuits, which they refined to be 10 times less energy consumptive. The project has yielded several scientific articles, in publications including Nature Communications.
Streaming films and music, scrolling through social media, and using cloud-based storage services are everyday activities now.
After helping develop a new approach for organic synthesis -- carbon-hydrogen functionalization -- scientists at Emory University are now showing how this approach may apply to drug discovery. Nature Catalysis published their most recent work -- a streamlined process for making a three-dimensional scaffold of keen interest to the pharmaceutical industry.
"Our tools open up whole new chemical space for potential drug targets," says Huw Davies, Emory professor of organic chemistry and senior author of the paper.
Superconductivity approaching room temperature may be possible in hydrogen-rich compounds at much lower pressures than previously expected
Reaching room-temperature superconductivity is one of the biggest dreams in physics. Its discovery would bring a technological revolution by providing...
12.02.2020 | Event News
16.01.2020 | Event News
15.01.2020 | Event News
18.02.2020 | Power and Electrical Engineering
18.02.2020 | Information Technology
18.02.2020 | Physics and Astronomy